A gas turbine as an example of rotary machines is configured to include a compressor that takes in and compresses air, a combustor that generates a high-temperature and high-pressure gas by injecting a fuel to the compressed air, and a turbine that is driven by the gas which is generated by the combustor. A single rotary shaft connects the compressor and the turbine to each other.
In general, it is desirable that the distance between the compressor and the turbine is set to be as short as possible so that the possibility of torsion or deflection in the rotary shaft is avoided.
The technique that is disclosed in, for example, PTL 1 is known in view of this requirement. According to the technique that is disclosed in PTL 1, respective output shafts of a motor, a compressor, and a clutch are configured to be connected to each other with couplings for the propagation of a rotational driving force.